Depends on what you like. In our house, deli mustard is what goes on the sandwiches.

If I was adventureous, I'd strain the fluid, mix in some beef base and reduce it to somewhere around a cup or less, add some vinegar, brown sugar and catsup simmering a bit more and start from there. Maybe add some paprika, onion and garlic powder and some Worchestershire sauce to that and see how the taste balances. Thicken with a little corn starch in cold water if necessary.

Sounds like a good sauce to work with, although I'm not sure the tase compliments the corn beef, but the spices in the broth would sort of make a nice tasting spicy catsup sauce for other meats

I have strained out the corned beef broth, and used it to make white beans several times. It's outstanding. Add chopped onion, celery, carrot, bay leaf, garlic, etc, just no more salt. Just like making bean soup, only thicker with no ham. Made a great lunch item. I forgot to save the broth from our beef today for that purpose...darn it.

I did have a chance to make some very good soda bread today, though. Never had done that before. Easy, and very good. The leftovers should make some good toast tomorrow morning.

I guess salty is subjective and maybe the brand of corned beef. The only two brands that can be found locally pre-prepared are Mosey's and Murphey & David's. I used to do my cabbage and carrots after cooking in the remaining broth and then switched to using a steam basket and steaming them instead with a collander. The main reason I steamed was to preserve the Old Bay and white pepper dusting that I gave the veggies which would probably be saltier then in the broth. From both of these brands and using their spice package, nobody ever complained about saltiness.

I too have used the broth for doing a Lima bean and barley soup sometimes with mushrooms many many times and nobody ever complained about the salinity and in this house that's an issue. Maybe some brands and their curing are much saltier.